If you read the service manual this is confusing. It will show the cam pulleys as left closest to the firewall. BUT in most other places the left hand components are actually on your right when facing the front of the engine. The exhaust manifolds are this way the left manifold is near the radiator. The valve covers are the same, left is the front of the car.

 

Yeah, that's the one I ordered… But the "Prime" seller (Amazon) wasn't available yesterday.. Just called Amazon, they said they just re-stocked them today. I purchased it from another seller on Amazon… Now I have to burn, burn, burn, gas until Wednesday (at the earliest)

 

Is it easiest enough to change this sensor out? I have a buddy who is very knowledgable with cars.. The first thing he told me is that I don't need the special tool… He has something that will work I guess.

Can it be changed from above? Without having to "lift" my car and having to do it from underneath? Can't seem to find a good youtube video…

 

It's relatively easy.

Here's a DIY to change from the top. https://www.clublexus.com/forums/es3...00-w-pics.html

I usually put my car on stands and access from the bottom.

You will likely need the O2 sensor removal tool.

 

Wow. Fantastic link you gave me. Can't wait for my sensor to show up so I can get going!

 

So now I'm concerned it might not be a bad sensor. I've found a couple places online that say just because an "OBD2" test says the problem is an O2 sensor, that doesn't necessarily mean the sensor is bad (see video link for one example)… Could be a faulty electrical connection TOO the sensor, or something?

Anyway, hope I didn't just waste $50.00 on a sensor that I don't need. Guess I won't know until I change it. Any thoughts on all this?

 

Yes it could be something else. But it is most likely the cause. O2 sensors typically last about 130,000 miles. If you have a 94 ES300 and the O2 sensor has never been replaced, now is as good as time as any to replace it. So your $50 is not wasted, think of it as preventive maintenance.

If you would list the exact error codes and symptoms, the Lexus community here could give you some better advice.

 

So I finally got my O2 sensor from Amazon (through seller "Gadget Mall" because Amazon didn't have any direct sales from themselves at the time).
Wow. What a joke… Check out the these pictures.. NOTHING like what was advertised.. A completely smashed up package, ripped up cord cover, no "end cap", looks like it's about 20+ years old (when I thought it was suppose to be new). I'd be surprised if it even works.. Even the anti-seize compound container is used/open.
Going to return it, and order one through Amazon (the actual seller) now that they have some available. Can I expect a better product?

 

While this is no consolation, I have received items that were clearly used, broken, or the wrong part in the correct package. Just go to Amazon and do a return. They will pay for return shipping and get a new part out right away.

It's not just Amazon where this occurs. It's all auto parts stores. Whenever I go to a brick and mortar store I inspect the item before I purchase it. On more than one occasion I'd arrive home with the wrong part or parts missing. It's a pain in the ***. One time I bought spark plugs in a box. When I opened them they were old and used. I'm sure some unscrupulous person returned them and the plugs were probably not inspected prior to being placed back on the self for resale.

Just this past week I returned a Ready Strut because the upper spring insulator failed in one day. They sent me a replacement in two days.

 

These O2 sensors have always confused me.
I have a 1999 ES300, california car. I already replaced the front O2 sensor (easiest one to replace) but before I go through the trouble of replacing the other 2. I want to make sure I buy the right ones.

I'm looking at this one for after the cat
http://www.ebay.com/itm/Lexus-ES300-LS400-Toyota-Camry-Solara-Oxygen-Sensor-Rear-Denso-2344137-/360710110861?hash=item53fbff7e8d&vxp=mtr
And this one for the rear

Looks good?

 

+1. You even have to inspect the seals on jugs of oil and ATF. People return their used stuff and the clerks accept it apparently without even looking at it.

 

Looks good.

 

i Got that same sensor from same dealer few days ago from ebay . No problems in product and shipping. But this one was for after catalytic converter and i had P0136 code. And to unplug is underneath the drivers seat.

 

Mission Accomplished.

Got my new sensor from Amazon. Changed it out in about 30 min. It wasn't too difficult. The old one came out pretty easy… Just one good solid turn of the socket wrench and it came loose. After changing it, my engine light stayed on for about 10-15 miles more… Made me a little nervous… seeing that red engine light starring me in the face even after I changed the sensor (even though I read it might take some time for it to go off)… But it finally did go off, and all is well!

Thanks everyone for all the input and advice.

Chris